On a 2003 lightning has anyone dynoed or track tested the stock exhaust system vs the flowmaster dual muffler setup.
Is there a true gain in power to be had over the stock muffler, other than a better sound? Any replies would be appreciated. William

 

Get anything else but Slowmasters. They don't do well on the L's. I had one on my truck and it sounded OK, but I went slower at the track. I switched to a dual Magnaflow setup, much better. Flowmasters sound good on other vehicles too, but I'm not too sure if they give any gain in HP.

 

I have flowmasters and as johny said they sound ok but ive also herd that you dont gain anything from them. The reason i bought them was for a cheap exhaust that sounded better then stock.

 

Guys, thanks for the feedback. In real numbers what is the loss at the track or on the dyno??
The reason i ask, its hard to feel a 10 horsepower loss or gain at the 400 hp level.
I'm really looking for quarter mile or 1/8 mile times or dyno #'s to compare.
The lightning i have has a 4# lower pulley with the HP4 superchip download.
The exhaust is an X pipe to 2 40 series delta flow flowmasters to dual outlets.
The system sound great but i did not run the vehicle at the track or dyno before & after the modifications. Thanks William